The invention relates to a monolithic integrated digital circuit comprising at least one data-processing circuit operating on a system clock signal, for multi-digit, data signals which contain very large numbers of digits.
Examples of such types of integrated digital circuits are signal processors and microprocessors which are commercially available. Further examples are integrated digital circuits forming part of a system consisting of several integrated circuits, and containing the corresponding data-processing circuits operating on a system clock signal, which are commercially available. One specific such system comprises several integrated circuits for the digital signal processing in television receivers, as described at pages 97 to 103 of "Electronics", Aug. 11, 1981. One essential feature of such integrated digital circuits is that multi-digit data signals are processed by the data-processing circuits in a parallel operation, that is, the multi-digit data signals are processed during a few clock periods in e.g. parallel adders, parallel multipliers, parallel comparators, etc.
Because parallel processing is used, the investment in crystal surface of the integrated digital circuit is large, so that semiconductor manufacturers will always tend to realize an electronic system which is to be integrated, having a small crystal surface area.
Another aspect of the integration of whole systems is the choice of the most suitable semiconductor integration technique. A determination must be made whether to use bipolar or MOS circuits with their respective specified subgroups, such as e.g. I.sup.2 L (bipolar) or N-channel, CMOS, etc., especially with a view to the maximum possible processing speeds peculiar to each of these integration techniques. In cases where the system clock frequency is defined on account of the respective system employed, for example, as with the aforementioned digital circuits for television receivers, this extensively determines the investment in crystal surface, because in the unanimous opinion of experts only a parallel processing of the data signals is feasible in the case of such high frequencies.